A "whistleblowers' roadshow" is to be launched to show civil servants how to raise concerns without contacting press or opposition MPs, it was disclosed.

The exhibition will highlight the network of senior officials who they can go to with their complaints.

"We are working to smarten up this process and create this network of nominated officers," said Cabinet Secretary Sir Andrew Turnbull.

The announcement came as Immigration Minister Beverley Hughes resigned.

Staff concerns

Her fate was sealed after two civil servants, one from the Home Office, the other from the Foreign Office, went public with concerns about the way the immigration service was operating.

She was finally forced to quit after she was reminded about correspondence a year ago with the then junior Home Office Minister Bob Ainsworth, who alerted her to concerns about visa applications from Romania and Bulgaria.

Earlier this week, Home Secretary David Blunkett offered staff a hotline to raise their concerns without fear of suspension.

But on Thursday, Sir Andrew told of government plans to organise "a series of roadshows" for civil servants, as he gave evidence to the Commons Public Administration Committee.

He said under Civil Service Code there was supposed to be a nominated official in each Whitehall department to deal with staff concerns.

'Neighbourly tensions'

But he conceded that some departments were better organised than others.

He said work was underway to create an electronic records system so that relevant documents on a particular subject could be quickly found by computer.

Sir Andrew said there were "clearly tensions" between 10 Downing Street and its neighbour, number 11 - the chancellor's office - over the direction of domestic policy.

But he insisted that such strains had historically always existed between the two neighbours.

"I don't deny the division between 10 and 11 is the San Andreas Fault of government," he said.